Replication Data for: Origin of (A)symmetry: The Evolution of Out-Party Distrust in the United States

Partisans tend to be skeptical of governments only when they are led by the other side. This president-in-power effect threatens democratic functioning by limiting partisans’ ability to hold their own party accountable. As polarization rises, the problems associated with this phenomenon are likely to aggravate. This paper examines the evolution and drivers of the president-in-power effect since 1974. Mirroring the general rise in polarization, we document a steady increase in the president-in-power effect. Our research demonstrates that this increase can be attributed to an intensification of partisan identification, combined with a growing perceived ideological distance towards the opposed party. Contrasting the narrative that polarization is stronger on the right, however, we find evidence that the president-in-power effect has grown faster for Democrats than for Republicans. To explain this pattern, we show that highly educated people, who display a stronger president-in-power effect, have shifted towards the left in recent years.党派支持者仅在对立党派掌权时，才会对政府持怀疑态度。这种执政党效应（president-in-power effect）会限制党派支持者监督本党的能力，进而威胁民主运行。随着政治极化（polarization）程度加剧，这一现象引发的问题可能会愈发严重。本文考察了1974年以来执政党效应的演变历程及其驱动因素。与整体政治极化的上升趋势相呼应，我们的研究记录了执政党效应的持续攀升。本研究表明，这一增长可归因于党派身份认同的强化，以及民众对对立党派意识形态差距感知的不断扩大。不过，与"右翼极化程度更为显著"的主流叙事相悖，我们的研究发现，民主党相关的执政党效应增长速度快于共和党。为解释这一规律，我们证实：近年来，表现出更强执政党效应的高学历群体，其政治立场已向左翼偏移。